1. Field of Invention:
This invention, about marine transportation of containers embodying the dual performance to haul and handle containers, more specifically applies to the exchange of containers to and from two floating carrier vessels disposed to opposite sides of a floating crane (third vessel). These three floating vessels are in mutual arrangement, being independent of tidal changes at alike offshore terminals, disposed globally. Offshore terminals, with one strategically located adjacent to each of many trade areas, establish a circuitous route for Cellers (subsequently defined) to ply. A preferred site, established in a protective cove, is selected remote to habitation and shipping lanes with indifference to land ruggedness or large bay characteristics. The offshore arrangement of transferring cargo between vessels avoids principal difficulties encountered during a voyage.
Vessels utilized herewith are identified to comply with names used in prior cross-references (subsequently listed). Similar to the concept of mammoth vessels with tanks being called "Tankers," so are super-ships with cells for containers more simply called "Cellers" herein. The term "barge" (as a towed vessel) is replaced by the symbol "LT" to be consistent with the disclosure of said cross-reference. Tugs also are as distinguishable in said cross-references. Tugs in tow of an LT as a combination defines the meaning of a "Feeder" as used herein. Floating cranes have an elevated craneway for a trolley with a hoisting means to exchange containers.
Feeders provide the direct exchange of containers (import and export cargo) at ports. With brief stops at each serviced port of trade area, the fleet size (more LTs than tugs) depends on the time lapse to provide a lay-to LT at an offshore terminal to await a Caller arrival. Feeders are the economical subordinate and supportive system for a fleet of Cellers repeating calls at many alike terminals (avoiding ports).
A Feeder bears export containerized cargo to a terminal and returns to port bearing import containerized cargo having had containers exchanged in the lay-to practice of the LT at a terminal. Cellers exchange certain of its (import) containerized cargo intended for that trade area for all export containerized cargo borne by the awaiting LT. The cyclical means effected between floating vessels for container exchanges to or from either vessel and ramifications therewith is the crux of this invention.
Cellers and Feeders, having specific functions, optimally serve to fulfill said dual performance cooperatively. This invention distinguishes in the mode of container handling as effected at offshore terminals. A facsimile system prescribes cell loading for a terminal by which the crane is disposed to handle containers.
2. Description of the Prior Art:
Standardized containers are uniformly eight feet wide and vary in length from 20 to 40 feet. They are constructed to be stacked one on top of another in a hull honeycombed with cells or on deck of vessels. Containers are lightly constructed to conserve weight and arranged with near corner devices to integrate a stack in regular coincidence. They are treated as fragile and sensitive to handle.
Supercontainerships serve their purpose at sea to transport vast tonnages at high speed, but just as with Tankers, are hard to maneuver particularly repective port consequentials of: comparative shallow water, tortuous passages, two way traffic, congestion and ramifications associated with shoreside facilities, marshalling areas and intermodal services.
Such shoreside consequences and capital intensive sites necessarily dictate supercontainership (noting Cellers are not so involved) be selective in ports of call. Thus some more near port of a trading area may be shunted for rail or truck intermodal means to more long distance haul containers to a port of call. Supercontainerships bear cargo handling gear, distinguishable from Cellers without such gear. Equipment to handle containers, most alike the present invention, are classified as double cantilever, through-leg gantry cranes of several variations. More commonly, these cranes are mounted on shoreside rails paralleling moored vessels for mobility fore and aft of the vessel and have craneways with hoist means to serve a vessel thwartwise.
When floating cranes serve to unload a vessel moored at its side, various supplementary dead-weight means are employed to counteract list tendency of the floating crane, when said hoist means is disposed on the craneway outboard of its hull.